(CNN) -- Nobel Prize laureate Mohamed ElBaradei has said he would run for the presidency of his native Egypt next year as long as he could be assured that the elections would be free and fair.

ElBaradei, who recently stepped down as head of the International Atomic Energy Agency, said he would seek to change the Egyptian constitution to allow international supervision of elections, an independent election commission and equal access to media.

It is the constitution, democracy activists say, that has allowed Egyptian President Hosni Mubarak to govern the country under emergency decree for nearly three decades, since the assassination of his predecessor Anwar Sadat.

"This is not my primary goal," ElBaradei said in an interview with CNN's Christiane Amanpour on Wednesday, "to run for the presidency. My primary goal is to see my country, Egypt, a country where I grew up, making a genuine shift toward democracy."

The 81-year-old Mubarak has not announced whether he would stand again for the presidency in 2011, but a succession of health challenges, including recent gall bladder surgery in Germany, have led Egyptians to discuss an issue that had long been off limits in the tightly controlled Egyptian press.

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"We have a president who has been in power for 30 years," ElBaradei said. "We have martial law for almost 30 years. This speaks volumes for the lack of democracy in Egypt."

ElBaradei, winner of the 2006 Nobel Peace Prize along with the IAEA, said he was organizing a grassroots movement across Egypt's political spectrum, using Facebook to petition to change the constitution in a manner that would open Egypt's political system to real pluralism.

"That current situation has to change, because the way it is crafted right now, it's only handful of people who have the right even to run for presidency. So democracy is no longer part of the Egyptian lifestyle for over 50 years. And it's an idea that its time has come."

ElBaradei does not have a political party, a factor that presents a substantive obstacle to his candidacy, but he vows to send a message of democratic change to the government.

"This is a peaceful, nonviolent movement, but it's a popular grassroots movement. And everywhere I go, everywhere I travel, there's massive support for change in Egypt."

"For the people, I'm a real agent for change. For the regime, I'm a virtual person," ElBaradei said. "I can't even have a headquarters. I can't raise funds. But we have a lot of volunteers. We have a lot of young volunteers everywhere in the country right now canvassing for change, explaining the people how change will impact on their economic and social life."

But Ahmed Ezz, a businessman and leading parliamentary member of the ruling National Democratic Party, said that ElBaradei was exaggerating the difficulty of competing in the upcoming elections.

"My party, the NDP, has made it clear it welcomes Dr. ElBaradei to join the political fray," Ezz said. "Our constitution anchors politics and political parties with clear political platforms. There are 24 parties in Egypt. Any of these parties can field candidates in 2011. Half of these parties, for example, have asked Dr. ElBaradei to be their candidate of choice. Dr. ElBaradei hesitates, preferring instead to run as an independent."

But Egyptian-American academic Saad Eddin Ibrahim, who spent three years in prison before being acquitted of charges of defaming the Egyptian state, said that ElBaradei was a charismatic candidate facing an enormous logistical challenge to organize a grassroots campaign.

"Mr. ElBaradei will have a good chance, and I think millions of Egyptians are willing to rally behind him," he said. "And if external powers could also demand that election, next election be free and fair and transparent, under international supervision, I think we have a very good chance of changing Egypt."